JP2005331408A - Instrument for measuring so3 concentration - Google Patents

Instrument for measuring so3 concentration Download PDF

Info

Publication number
JP2005331408A
JP2005331408A JP2004150832A JP2004150832A JP2005331408A JP 2005331408 A JP2005331408 A JP 2005331408A JP 2004150832 A JP2004150832 A JP 2004150832A JP 2004150832 A JP2004150832 A JP 2004150832A JP 2005331408 A JP2005331408 A JP 2005331408A
Authority
JP
Japan
Prior art keywords
concentration
measuring
dew point
acid dew
exhaust gas
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
JP2004150832A
Other languages
Japanese (ja)
Inventor
Hirokazu Hanato
弘和 花登
Koji Terai
孝治 寺井
Hitoshi Takase
等 高瀬
Hiroyuki Inagaki
裕行 稲垣
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kansai Electric Power Co Inc
Original Assignee
Kansai Electric Power Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kansai Electric Power Co Inc filed Critical Kansai Electric Power Co Inc
Priority to JP2004150832A priority Critical patent/JP2005331408A/en
Publication of JP2005331408A publication Critical patent/JP2005331408A/en
Withdrawn legal-status Critical Current

Links

Images

Landscapes

  • Investigating Or Analyzing Materials Using Thermal Means (AREA)
  • Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide an SO<SB>3</SB>concentration measuring instrument capable of continuously measuring SO<SB>3</SB>concentration. <P>SOLUTION: This SO<SB>3</SB>concentration measuring instrument for measuring the SO<SB>3</SB>concentration in an exhaust gas includes a sulfuric acid dew point measuring means for measuring a sulfuric acid dew point in the exhaust gas; a moisture concentration measuring means for measuring a moisture concentration in the exhaust gas; and an SO<SB>3</SB>concentration computing means for computing the SO<SB>3</SB>concentration, based on the sulfuric acid dew point measured by the sulfuric acid dew point measuring means, and based on the moisture concentration measured by the moisture concentration measuring means. Preferably, the SO<SB>3</SB>concentration is computed therein, after a time shift between a measuring time for the sulfuric acid dew point by the sulfuric acid dew point measuring means, and a measurement time for the moisture concentration by the moisture concentration measuring means is corrected. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明はＳＯ3（三酸化硫黄）濃度計測装置に関し、特にＳＯ3濃度を連続して計測することができるＳＯ3濃度計測装置に関する。 The present invention relates to SO 3 (sulfur trioxide) concentration measuring apparatus, and SO 3 concentration measuring apparatus, in particular can be measured continuously SO 3 concentration.

化石燃料、たとえば石油を燃料とするボイラの排ガス内にはＳＯ3が含まれているが、ＳＯ3は排ガス中の水分と激しく反応してＨ2ＳＯ4（硫酸）を生成し、このＨ2ＳＯ4によって鉄製品が腐食されるという問題が生じている。 Fossil fuels, for example in the exhaust gas of the boiler that burns oil contains SO 3, SO 3 generates H 2 SO 4 and reacts violently with water in the exhaust gas (sulfuric acid), the H 2 There is a problem that iron products are corroded by SO 4 .

特に、高硫黄分燃料焚発電プラントでは、ボイラから排出される排ガス中のＳＯ3による電気集塵装置や煙道の低温腐食が問題となる。通常、この低温腐食を防止するために、アンモニア（ＮＨ3）を煙道に注入してＳＯ3を中和して（ＮＨ4）2ＳＯ4（硫酸アンモニウム）とし、これを電気集塵装置で回収することが行なわれている。ここで、ＮＨ3の注入量が多すぎると環境に悪影響を及ぼし、ＮＨ3の注入量が少なすぎると低温腐食を抑止することができないことから、ＮＨ3の注入量を適正にする上で、ＳＯ3濃度を連続して計測することは非常に重要である。 In particular, in a high-sulfur fuel-fired power plant, low temperature corrosion of the electric dust collector and flue due to SO 3 in the exhaust gas discharged from the boiler becomes a problem. Normally, in order to prevent this low temperature corrosion, ammonia (NH 3 ) is injected into the flue to neutralize SO 3 to (NH 4 ) 2 SO 4 (ammonium sulfate), which is collected by an electrostatic precipitator. To be done. Here, the injection amount of the NH 3 is too large an adverse effect on the environment, the amount of injected NH 3 is too small from the inability to suppress low-temperature corrosion, in terms of the proper amount of injected NH 3, It is very important to continuously measure the SO 3 concentration.

従来、排ガス中のＳＯ3濃度の計測には、酸凝縮法、イソプロピルアルコール（ＩＰＡ）吸収法、加熱食塩法またはＮＨ3注入法などが用いられていた。 Conventionally, an acid condensation method, an isopropyl alcohol (IPA) absorption method, a heated salt method, an NH 3 injection method, or the like has been used for measuring the SO 3 concentration in exhaust gas.

酸凝縮法は排ガス中のＳＯ3を計測管の内壁に凝縮させて捕集し、滴定によりＳＯ3濃度を計測する方法である。また、ＩＰＡ吸収法は、排ガス中のＳＯ3をＩＰＡ溶液に吸収させ、ＩＰＡ溶液中のＨ2ＳＯ4濃度を滴定により定量することによってＳＯ3濃度を計測する方法である。また、加熱食塩法は、排ガス中のＳＯ3とＮａＣｌ（塩化ナトリウム）とを反応させてＨＣｌ（塩酸）を生成し、このＨＣｌ濃度を滴定により定量することによってＳＯ3濃度を計測する方法である。さらに、ＮＨ3注入法は、ＳＯ3を含む排ガス中にＮＨ3を吹き込むことによって（ＮＨ4）2ＳＯ4を生成し、余剰のＮＨ3濃度からＳＯ3濃度を推定する方法である。 The acid condensation method is a method in which SO 3 in exhaust gas is condensed and collected on the inner wall of a measurement tube and the SO 3 concentration is measured by titration. The IPA absorption method is a method of measuring the SO 3 concentration by absorbing SO 3 in exhaust gas into an IPA solution and quantifying the H 2 SO 4 concentration in the IPA solution by titration. The heated salt method is a method of measuring SO 3 concentration by reacting SO 3 in exhaust gas with NaCl (sodium chloride) to produce HCl (hydrochloric acid), and quantifying this HCl concentration by titration. . Further, NH 3 injection method, by blowing NH 3 in the exhaust gas containing the SO 3 to produce a (NH 4) 2 SO 4, is a method of estimating the SO 3 concentration of NH 3 concentration of excess.

しかしながら、これらの方法においては、その計測原理上、排ガス中のＳＯ3濃度を連続して計測することが困難であるという問題があった。 However, these methods have a problem that it is difficult to continuously measure the SO 3 concentration in the exhaust gas due to the measurement principle.

そこで、ＳＯ3濃度を連続して計測する装置として、たとえば、特許文献１には、ミスト化したＳＯ3の濃度を測定するための光学式粒子濃度計を含むＳＯ3濃度測定装置が開示されている。また、特許文献２には、反射ミラーによってキャビティ内を複数回往復させた後の光を分光分析することによってＳＯ3濃度を連続して計測するＳＯ3濃度計が開示されている。さらに、特許文献３には、妨害ガスとなるＳＯ2（二酸化硫黄）を混入したガスでＳＯ3の組成比を変えながら吸光度スペクトルをとり、その吸光度スペクトルデータを基にして作成した検量線を用いて、紫外線吸収分析することにより連続して煙道中のＳＯ3濃度を算出する方法が開示されている。 Therefore, as an apparatus for continuously measuring the SO 3 concentration, for example, Patent Document 1 discloses SO 3 concentration measuring apparatus comprising an optical particle concentration meter for measuring the concentration of SO 3 which is mist is disclosed Yes. Further, Patent Document 2, SO 3 concentration meter for measuring continuously SO 3 concentration is disclosed by the light after being reciprocally multiple times within the cavity for spectroscopic analysis by the reflection mirror. Furthermore, Patent Document 3 uses a calibration curve created on the basis of the absorbance spectrum data obtained by taking an absorbance spectrum while changing the composition ratio of SO 3 with a gas mixed with SO 2 (sulfur dioxide) as an interfering gas. Thus, a method for continuously calculating the SO 3 concentration in the flue by performing ultraviolet absorption analysis is disclosed.

しかしながら、これらの特許文献１〜３に開示されている技術においては、主に光を用いてＳＯ3濃度を計測しているため、ＳＯ3濃度の計測途中における光の損失などによって正確なＳＯ3濃度を計測することができないことがあった。
特開２００３−１３０７６８号公報 特開２００１−１８８０４０号公報 特開２００１−１８８０４３号公報 However, in the techniques disclosed in these Patent Documents 1 to 3, since the SO 3 concentration is mainly measured by using light, an accurate SO 3 is measured due to light loss during the measurement of the SO 3 concentration. In some cases, the concentration could not be measured.
JP 2003-130768 A JP 2001-188040 A JP 2001-188043 A

本発明の目的は、ＳＯ3濃度を連続して計測することができるＳＯ3濃度計測装置を提供することにある。 An object of the present invention is to provide a SO 3 concentration measuring device capable of measuring continuously the SO 3 concentration.

本発明は、排ガス中のＳＯ3の濃度を計測するＳＯ3濃度計測装置であって、排ガスの酸露点を計測する酸露点計測手段と、排ガス中の水分濃度を計測する水分濃度計測手段と、
酸露点計測手段によって計測された酸露点と水分濃度計測手段によって計測された水分濃度とからＳＯ3濃度を演算するＳＯ3濃度演算手段とを含むＳＯ3濃度計測装置である。 The present invention relates to a SO 3 concentration measuring device for measuring the concentration of SO 3 in the exhaust gas, and the acid dew point measuring means for measuring the acid dew point of the exhaust gas, and water concentration measuring means for measuring a water concentration in the exhaust gas,
Is SO 3 concentration measuring device comprising a SO 3 concentration calculating means for calculating a SO 3 concentration and a water concentration measured by the dew point measured by the dew point measuring means and the moisture concentration measuring unit.

ここで、本発明のＳＯ3濃度計測装置においては、酸露点計測手段による酸露点の計測時間と水分濃度計測手段による水分濃度の計測時間とのずれを補正してＳＯ3濃度が演算されることが好ましい。 Here, in the SO 3 concentration measuring apparatus of the present invention, the SO 3 concentration is calculated by correcting the deviation between the acid dew point measuring time by the acid dew point measuring means and the water concentration measuring time by the water concentration measuring means. Is preferred.

また、本発明のＳＯ3濃度計測装置においては、ＳＯ3濃度演算手段によるＳＯ3濃度の演算は、 Further, the SO 3 concentration measuring apparatus of the present invention, the operation of the SO 3 concentration by SO 3 concentration calculating means,

Figure 2005331408
Figure 2005331408

の式（１）を用いて行なわれることが好ましい。 It is preferable to use the following formula (1).

本発明によれば、ＳＯ3濃度を連続して計測することができるＳＯ3濃度計測装置を提供することができる。したがって、本発明によれば、排ガス中のＳＯ3濃度をリアルタイムで計測することができるため、煙道へのＮＨ3の注入量を適正にすることができる。これにより、電気集塵装置や煙道の低温腐食を抑止することができるとともに環境への悪影響も回避することもできる。 According to the present invention, it is possible to provide a SO 3 concentration measuring device capable of measuring continuously the SO 3 concentration. Therefore, according to the present invention, since the SO 3 concentration in the exhaust gas can be measured in real time, the amount of NH 3 injected into the flue can be made appropriate. As a result, low-temperature corrosion of the electrostatic precipitator and the flue can be suppressed, and adverse effects on the environment can be avoided.

以下、本発明の実施の形態について説明する。なお、本願の図面において、同一の参照符号は、同一部分または相当部分を表わすものとする。   Hereinafter, embodiments of the present invention will be described. In the drawings of the present application, the same reference numerals denote the same or corresponding parts.

図１に本発明のＳＯ3濃度計測装置の好ましい一例の構成図を示す。図１において、本発明のＳＯ3濃度計測装置は、酸露点計測手段としての酸露点計１と、水分濃度計測手段としての水分計２と、ＳＯ3濃度演算手段としての演算器３とを含む。 FIG. 1 shows a configuration diagram of a preferred example of the SO 3 concentration measuring apparatus of the present invention. 1, the SO 3 concentration measuring apparatus of the present invention includes an acid dew point meter 1 as an acid dew point measuring unit, a moisture meter 2 as a moisture concentration measuring unit, and a calculator 3 as an SO 3 concentration calculating unit. .

このＳＯ3濃度計測装置においては、煙道４を流れる排ガス５の酸露点を酸露点計１によって計測し、排ガス５中の水分濃度を水分計２によって計測する。そして、計測された酸露点および水分濃度が演算器３に入力され、演算器３によってＳＯ3濃度が演算された後にＳＯ3濃度が出力される。 In this SO 3 concentration measuring device, the acid dew point of the exhaust gas 5 flowing through the flue 4 is measured by the acid dew point meter 1, and the moisture concentration in the exhaust gas 5 is measured by the moisture meter 2. Then, the measured acid dew point and water concentration are input to the calculator 3, and after the SO 3 concentration is calculated by the calculator 3 , the SO 3 concentration is output.

図２（Ａ）に本発明に用いられる酸露点計の一例の概念図を示し、図２（Ｂ）にこの酸露点計のプローブ部の先端の平面図を示す。酸露点計１は、プローブ部６と、電気制御ユニット７と、空気制御ユニット８とを含む。そして、プローブ部６が煙道に挿入され、プローブ部６の先端にある検出部９の表面を冷却用ノズル１０から放出される冷却用空気１１によって冷却し、検出部９の表面温度が排ガスの酸露点温度以下になるとＨ2ＳＯ4が凝縮し、Ｈ2ＳＯ4膜１２が形成される。検出部９の表面温度が排ガスの酸露点に調節されたときには、検出部９の表面における酸の凝縮率と蒸発率とが等しくなるため、形成されたＨ2ＳＯ4膜１２の膜厚が一定となる。一方、Ｈ2ＳＯ4膜１２の膜厚が一定である場合には、Ｈ2ＳＯ4膜１２を流れる電流量も一定となる。そこで、酸露点計１においては、検出部９の表面上のＨ2ＳＯ4膜１２を流れる電流量が一定となるように冷却用空気１１の放出量が調節され、Ｈ2ＳＯ4膜１２を流れる電流量が一定であるときの検出部９の表面温度が酸露点として計測される。 FIG. 2A shows a conceptual diagram of an example of the acid dew point meter used in the present invention, and FIG. 2B shows a plan view of the tip of the probe portion of the acid dew point meter. The acid dew point meter 1 includes a probe unit 6, an electric control unit 7, and an air control unit 8. Then, the probe unit 6 is inserted into the flue, the surface of the detection unit 9 at the tip of the probe unit 6 is cooled by the cooling air 11 discharged from the cooling nozzle 10, and the surface temperature of the detection unit 9 is reduced to the exhaust gas. When the temperature is lower than the acid dew point temperature, H 2 SO 4 is condensed and an H 2 SO 4 film 12 is formed. When the surface temperature of the detection unit 9 is adjusted to the acid dew point of the exhaust gas, the acid condensation rate and the evaporation rate on the surface of the detection unit 9 become equal, so the film thickness of the formed H 2 SO 4 film 12 is constant. It becomes. On the other hand, when the thickness of the H 2 SO 4 film 12 is constant, the amount of current flowing in the H 2 SO 4 film 12 is also constant. Therefore, in the acid dew point meter 1, the discharge amount of the cooling air 11 is adjusted so that the amount of current flowing through the H 2 SO 4 film 12 on the surface of the detector 9 is constant, and the H 2 SO 4 film 12 is The surface temperature of the detection unit 9 when the amount of flowing current is constant is measured as the acid dew point.

ここで、プローブ部６の先端にある検出部９は、熱電対１３と、熱電対１３の周囲を取り囲むようにして形成されているリング電極１４と、熱電対１３とリング電極１４との間およびリング電極１４の周囲に形成されている絶縁性部材１５とから構成される。そして、Ｈ2ＳＯ4膜１２を流れる電流量としては、リング電極１４と熱電対１３の負極との間に流れる電流値（以下、「電極電流値」という。）が測定される。 Here, the detection unit 9 at the tip of the probe unit 6 includes a thermocouple 13, a ring electrode 14 formed so as to surround the thermocouple 13, and between the thermocouple 13 and the ring electrode 14. The insulating member 15 is formed around the ring electrode 14. As the amount of current flowing through the H 2 SO 4 film 12, the value of current flowing between the ring electrode 14 and the negative electrode of the thermocouple 13 (hereinafter referred to as “electrode current value”) is measured.

また、熱電対１３、リング電極１４および絶縁性部材１５は、酸露点計１の耐久性を向上させる観点から、酸に対して耐食性を有する材質で形成されることが好ましい。たとえば、熱電対１３の材質としては、負極にプラチナ（Ｐｔ）を用い、正極にプラチナ−ロジウム合金（ＰｔＲｈ）を用いることが好ましい。また、リング電極１４の材質としては、プラチナ（Ｐｔ）を用いることが好ましい。さらに、絶縁性部材１５の材質としては、ホウ珪酸塩ガラス（二酸化珪素に網目形成酸化物としてホウ素を混ぜたもの）を用いることが好ましい。   In addition, the thermocouple 13, the ring electrode 14, and the insulating member 15 are preferably formed of a material that is resistant to acid from the viewpoint of improving the durability of the acid dew point meter 1. For example, as the material of the thermocouple 13, it is preferable to use platinum (Pt) for the negative electrode and platinum-rhodium alloy (PtRh) for the positive electrode. Moreover, as a material of the ring electrode 14, it is preferable to use platinum (Pt). Further, as the material of the insulating member 15, borosilicate glass (a mixture of silicon dioxide and boron as a network-forming oxide) is preferably used.

電気制御ユニット７は、排ガスの酸露点を計測する機能と、Ｈ2ＳＯ4膜１２を流れる電流量の計測によって冷却用空気１１の放出量を制御する機能とを有する。 The electric control unit 7 has a function of measuring the acid dew point of the exhaust gas and a function of controlling the discharge amount of the cooling air 11 by measuring the amount of current flowing through the H 2 SO 4 film 12.

図３に電気制御ユニット７による冷却用空気１１の放出量の制御の一例のフローチャートを示す。   FIG. 3 shows a flowchart of an example of control of the discharge amount of the cooling air 11 by the electric control unit 7.

まず、ステップ（以下、「Ｓ」と略す場合がある。）１０１において冷却用空気の放出量を増加させると、Ｓ１０２において検出部の表面温度が低下する。すると、Ｈ2ＳＯ4の凝縮率が増大するため、Ｓ１０３においてＨ2ＳＯ4膜の膜厚が厚くなる。それに伴い、Ｓ１０４においてＨ2ＳＯ4膜を流れる電流量が増加するため、Ｓ１０５において電極電流値が増加する。そして、Ｓ１０６において電極電流値が所定の電流値（たとえば１００μＡ）以上でない場合（ＮＯ）にはＳ１０１に戻って再度Ｓ１０１以降のステップが繰り返される。 First, when the amount of cooling air released is increased in step (hereinafter may be abbreviated as “S”) 101, the surface temperature of the detection unit is decreased in S102. Then, since the condensation rate of H 2 SO 4 increases, the film thickness of the H 2 SO 4 film increases in S103. Accordingly, the amount of current flowing through the H 2 SO 4 film increases in S104, and thus the electrode current value increases in S105. If the electrode current value is not equal to or greater than a predetermined current value (for example, 100 μA) in S106 (NO), the process returns to S101 and the steps after S101 are repeated again.

他方、Ｓ１０６において電極電流値が所定の電流値（たとえば１００μＡ）以上である場合（ＹＥＳ）にはＳ１０７において冷却用空気の放出量を減少させる。すると、Ｓ１０８において検出部の表面温度が上昇し、Ｈ2ＳＯ4の凝縮率が減少するため、Ｓ１０９においてＨ2ＳＯ4膜の膜厚が薄くなる。それに伴い、Ｓ１１０においてＨ2ＳＯ4膜を流れる電流量が減少するため、Ｓ１１１において電極電流値が減少する。そして、Ｓ１１２において電極電流値が所定の電流値（たとえば１００μＡ）未満でない場合（ＮＯ）にはＳ１０７に戻って再度Ｓ１０７からＳ１１２が繰り返される。他方、Ｓ１１２において電極電流値が所定の電流値（たとえば１００μＡ）未満である場合（ＹＥＳ）にはＳ１０１に戻って再度Ｓ１０１以降のステップが繰り返される。 On the other hand, when the electrode current value is equal to or greater than a predetermined current value (for example, 100 μA) in S106 (YES), the amount of cooling air released is decreased in S107. Then, the surface temperature of the detection unit rises in S108 and the condensation rate of H 2 SO 4 decreases, so that the film thickness of the H 2 SO 4 film becomes thinner in S109. Accordingly, the amount of current flowing through the H 2 SO 4 film decreases in S110, and thus the electrode current value decreases in S111. If the electrode current value is not less than a predetermined current value (for example, 100 μA) in S112 (NO), the process returns to S107 and S107 to S112 are repeated again. On the other hand, when the electrode current value is less than a predetermined current value (for example, 100 μA) in S112 (YES), the process returns to S101 and the steps after S101 are repeated again.

図２（Ａ）に示す電気制御ユニット７による冷却用空気１１の放出量を増減させる制御信号は、空気制御ユニット８に入力され、空気制御ユニット８中の冷却用空気制御弁１６を開閉することによって冷却用空気１１の放出量の増減が調節される。なお、正確なＳＯ3濃度を計測し、メンテナンスを容易にする観点から、空気制御ユニット８は検出部９の表面を洗浄することができる洗浄システムを有していることが好ましい。 A control signal for increasing or decreasing the discharge amount of the cooling air 11 by the electric control unit 7 shown in FIG. 2A is input to the air control unit 8 to open and close the cooling air control valve 16 in the air control unit 8. Thus, the increase / decrease of the discharge amount of the cooling air 11 is adjusted. Note that, from the viewpoint of measuring an accurate SO 3 concentration and facilitating maintenance, the air control unit 8 preferably has a cleaning system that can clean the surface of the detection unit 9.

図４に、本発明に用いられる水分計の一例の概念図を示す。水分計２としては、たとえばジルコニア式水分計が用いられる。ジルコニア式水分計は、２台のジルコニア酸素計を用いて、排ガス（湿りガス）中の酸素濃度（Ｏ2ｗ）と、湿りガスの水分を除湿部において除去した後の排ガス（乾きガス）中の酸素濃度（Ｏ2ｄ）とを計測し、これらの酸素濃度から水分濃度（Ｃｗ（ｔ））を演算するものである。 In FIG. 4, the conceptual diagram of an example of the moisture meter used for this invention is shown. As the moisture meter 2, for example, a zirconia moisture meter is used. The zirconia moisture meter uses two zirconia oxygen meters to measure the oxygen concentration (O 2 w) in the exhaust gas (wet gas) and the exhaust gas (dry gas) after removing the moisture of the wet gas in the dehumidifying section. The oxygen concentration (O 2 d) is measured, and the water concentration (Cw (t)) is calculated from these oxygen concentrations.

すなわち、湿りガスの水分以外のガスの割合（１００−Ｃｗ（ｔ））に対する酸素の割合と、乾きガス中に存在する酸素の割合とが等しいことから、下記式（２）が成立する。   That is, since the ratio of oxygen to the ratio of gas other than moisture (100-Cw (t)) of the wet gas is equal to the ratio of oxygen present in the dry gas, the following formula (2) is established.

Figure 2005331408
Figure 2005331408

そして、この式を変形して得られた下記式（３）により、水分濃度（Ｃｗ（ｔ））が演算されることとなる。   Then, the moisture concentration (Cw (t)) is calculated by the following equation (3) obtained by modifying this equation.

Figure 2005331408
Figure 2005331408

なお、ジルコニア酸素計は、たとえばジルコニア素子の内外面に電極が形成されて構成される。ジルコニア素子の内外に酸素濃度の異なるガス（排ガスと空気）を接触させると、酸素分圧の高い電極で酸素分子が電子を得て酸素イオンとなり、このイオンがジルコニア素子内を移動し、他方の電極に至って電子を放出して酸素分子に戻る。この反応で両電極間に生じる電圧（Ｅ（ｍＶ））を下記式（４）（Ｎｅｒｎｓｔの式）に代入することによって酸素濃度（ＰＯ2）が演算される。 The zirconia oximeter is configured, for example, by forming electrodes on the inner and outer surfaces of a zirconia element. When gases with different oxygen concentrations (exhaust gas and air) are brought into contact with the inside and outside of the zirconia element, oxygen molecules get electrons and become oxygen ions at the electrode having a high oxygen partial pressure, and these ions move inside the zirconia element, It reaches the electrode and emits electrons to return to oxygen molecules. By substituting the voltage (E (mV)) generated between both electrodes in this reaction into the following equation (4) (Nernst equation), the oxygen concentration (P O2 ) is calculated.

Figure 2005331408
Figure 2005331408

上述のようにして得られた酸露点と水分濃度とから、図１に示す演算器３において、ＳＯ3濃度が演算される。ここで、演算式としては、下記式（５）（Ｖｅｒｈｏｆｆの経験式）を実験結果から修正した下記式（６）（修正式）が用いられる。 From the acid dew point and the moisture concentration obtained as described above, the SO 3 concentration is calculated in the calculator 3 shown in FIG. Here, the following formula (6) (corrected formula) obtained by correcting the following formula (5) (Verhoff's empirical formula) from the experimental results is used as the arithmetic formula.

Figure 2005331408
Figure 2005331408

Figure 2005331408
Figure 2005331408

ここで、図１に示す演算器３におけるＳＯ3濃度の演算は、酸露点計１による酸露点の計測時間と、水分計２による水分濃度の計測時間とのずれを補正して行なわれることが好ましい。この場合には、酸露点計１による酸露点と水分計２による水分濃度との同時性を確保することができるため、より正確にＳＯ3濃度の演算をすることができるようになる。 Here, the calculation of the SO 3 concentration in the calculator 3 shown in FIG. 1 may be performed by correcting the difference between the measurement time of the acid dew point by the acid dew point meter 1 and the measurement time of the water concentration by the moisture meter 2. preferable. In this case, since the synchronism between the acid dew point by the acid dew point meter 1 and the water concentration by the moisture meter 2 can be ensured, the SO 3 concentration can be calculated more accurately.

たとえば、酸露点計１と水分計２とが上述のような構成を有している場合には、図２に示す酸露点計においてはプローブ部を煙道に直接挿入して酸露点が計測されるためほとんど検出遅れがないのに対し、図４に示す水分計においては煙道から排ガスを水分計内に取り込んで湿りガス中における酸素濃度と、湿りガスを除湿した後の乾きガス中における酸素濃度とが順次計測されるため、酸露点計よりも検出遅れが生じることになる。   For example, when the acid dew point meter 1 and the moisture meter 2 have the above-described configuration, in the acid dew point meter shown in FIG. 2, the acid dew point is measured by directly inserting the probe portion into the flue. Therefore, in the moisture meter shown in FIG. 4, the exhaust gas is taken into the moisture meter from the flue and the oxygen concentration in the wet gas and the oxygen in the dry gas after dehumidifying the wet gas are present. Since the concentration is sequentially measured, a detection delay is generated as compared with the acid dew point meter.

したがって、たとえば、ＳＯ3濃度と水分濃度とが何らかの外乱により図５に示すような変化をしたとき、酸露点計の出力はＳＯ3濃度の変化に応じてすぐに変化するのに対し、水分濃度の出力は水分濃度の変化に応じてすぐに変化せず、酸露点計の出力に対してたとえばＴ秒の応答時間差を生じることとなる。 Therefore, for example, when the SO 3 concentration and the water concentration change as shown in FIG. 5 due to some disturbance, the output of the acid dew point meter immediately changes according to the change in the SO 3 concentration, whereas the water concentration Output does not change immediately according to the change in moisture concentration, and a response time difference of, for example, T seconds is generated with respect to the output of the acid dew point meter.

このＴ秒の応答時間差を考慮して上記修正式を変形した下記式（１）（新修正式）を用いてＳＯ3濃度を演算することによって、より正確なＳＯ3濃度の演算をすることができるようになる。 It is possible to calculate the SO 3 concentration more accurately by calculating the SO 3 concentration using the following equation (1) (new correction equation) obtained by modifying the correction equation in consideration of the response time difference of T seconds. become able to.

Figure 2005331408
Figure 2005331408

このようにして演算されたＳＯ3濃度に応じてＮＨ3の注入量を適正化することによって、ＳＯ3による電気集塵装置や煙道の低温腐食を抑止することができるとともにＮＨ3の過剰注入による環境への悪影響も回避することもできるようになる。 By optimizing the NH 3 injection amount according to the calculated SO 3 concentration in this way, the low temperature corrosion of the electrostatic precipitator and the flue due to SO 3 can be suppressed and the NH 3 is excessively injected. It will also be possible to avoid the negative impact on the environment.

なお、ＮＨ3の注入によるＳＯ3の除去は、下記化学反応式に基づく反応をさせ、ＳＯ3を（ＮＨ4）2ＳＯ4として除去することにより行なわれる。
２ＮＨ3＋ＳＯ3＋Ｈ2Ｏ→（ＮＨ4）2ＳＯ4 The removal of SO 3 by NH 3 injection is performed by performing a reaction based on the following chemical reaction formula and removing SO 3 as (NH 4 ) 2 SO 4 .
2NH 3 + SO 3 + H 2 O → (NH 4 ) 2 SO 4

（実施例１）
図１に示す本発明のＳＯ3濃度計測装置を用いて、ＳＯ3濃度の計測を行なった。ここで、排ガスにはＳＯ3濃度が３４．２ｐｐｍである２００℃の排ガスを用い、この排ガスを１Ｌ／ｍｉｎの流量で煙道に１０分間流し続け、この間のＳＯ3濃度の計測を連続して行なった。その結果を表１に示す。表１に示すように、本発明のＳＯ3濃度計測装置によって計測されたＳＯ3濃度は３４ｐｐｍであって、実際のＳＯ3濃度とは０．２ｐｐｍの濃度差しかなかった。 (Example 1)
Using the SO 3 concentration measuring apparatus of the present invention shown in FIG. 1, the SO 3 concentration was measured. Here, exhaust gas at 200 ° C. with an SO 3 concentration of 34.2 ppm was used as exhaust gas, and this exhaust gas was continuously supplied to the flue at a flow rate of 1 L / min for 10 minutes, and the measurement of SO 3 concentration during this time was continuously performed. I did it. The results are shown in Table 1. As shown in Table 1, SO 3 concentration measured by the SO 3 concentration measuring apparatus of the present invention is a 34 ppm, the actual SO 3 concentration was only density difference 0.2 ppm.

ここで、表１に示すＳＯ3濃度計測装置のＳＯ3濃度は、１０分間の計測中に最も安定して表示された値を表わしている。また、本発明のＳＯ3濃度計測装置におけるＳＯ3濃度の演算には酸露点計と水分計との応答誤差を考慮した上記式（１）（新修正式）を用いた。 Here, SO 3 concentration of SO 3 concentration measuring device shown in Table 1 represents the most stable value displayed in the 10 minutes measurement. In addition, the calculation of SO 3 concentration in the SO 3 concentration measuring apparatus of the present invention uses the above equation (1) (new correction equation) in consideration of the response error between the acid dew point meter and the moisture meter.

（実施例２）
ＳＯ3濃度が７７．４ｐｐｍである排ガスを用いたこと以外は、実施例１と同様にしてＳＯ3濃度の計測を連続して行なった。その結果を表１に示す。表１に示すように、本発明のＳＯ3濃度計測装置によって計測されたＳＯ3濃度は７８．３ｐｐｍであって、実際のＳＯ3濃度とは０．９ｐｐｍの濃度差しかなかった。 (Example 2)
Except that SO 3 concentration using the exhaust gas is 77.4Ppm, it was carried out continuously measuring the SO 3 concentration in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, SO 3 concentration measured by the SO 3 concentration measuring apparatus of the present invention is a 78.3Ppm, the actual SO 3 concentration was only density difference 0.9 ppm.

（実施例３）
ＳＯ3濃度が２１．３ｐｐｍである排ガスを用いたこと以外は、実施例１と同様にしてＳＯ3濃度の計測を連続して行なった。その結果を表１に示す。表１に示すように、本発明のＳＯ3濃度計測装置によって計測されたＳＯ3濃度は２１．２ｐｐｍであって、実際のＳＯ3濃度とは０．１ｐｐｍの濃度差しかなかった。 (Example 3)
Except that SO 3 concentration using the exhaust gas is 21.3Ppm, it was carried out continuously measuring the SO 3 concentration in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, SO 3 concentration measured by the SO 3 concentration measuring apparatus of the present invention is a 21.2Ppm, the actual SO 3 concentration was only density difference 0.1 ppm.

（実施例４）
ＳＯ3濃度が９２．２ｐｐｍである１６５℃の排ガスを用いたこと以外は、実施例１と同様にしてＳＯ3濃度の計測を連続して行なった。その結果を表１に示す。表１に示すように、本発明のＳＯ3濃度計測装置によって計測されたＳＯ3濃度は９３．１ｐｐｍであって、実際のＳＯ3濃度とは０．９ｐｐｍの濃度差しかなかった。 Example 4
Except that SO 3 concentration was used 165 ° C. of the exhaust gas is 92.2ppm was performed continuously measuring the SO 3 concentration in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, SO 3 concentration measured by the SO 3 concentration measuring apparatus of the present invention is a 93.1Ppm, the actual SO 3 concentration was only density difference 0.9 ppm.

（実施例５）
ＳＯ3濃度が５４．９ｐｐｍである１６５℃の排ガスを用いたこと以外は、実施例１と同様にしてＳＯ3濃度の計測を連続して行なった。その結果を表１に示す。表１に示すように、本発明のＳＯ3濃度計測装置によって計測されたＳＯ3濃度は５４．３ｐｐｍであって、実際のＳＯ3濃度とは０．６ｐｐｍの濃度差しかなかった。 (Example 5)
Except that SO 3 concentration was used 165 ° C. of the exhaust gas is 54.9ppm was performed continuously measuring the SO 3 concentration in the same manner as in Example 1. The results are shown in Table 1. As shown in Table 1, SO 3 concentration measured by the SO 3 concentration measuring apparatus of the present invention is a 54.3Ppm, the actual SO 3 concentration was only density difference 0.6 ppm.

Figure 2005331408
Figure 2005331408

表１に示すように、実施例１〜５において、本発明のＳＯ3濃度計測装置を用いて計測されたＳＯ3濃度と実際のＳＯ3濃度との濃度差はすべて１ｐｐｍ未満であった。 As shown in Table 1, in Examples 1 to 5, the density difference between the actual SO 3 concentration and SO 3 concentration was measured using the SO 3 concentration measuring apparatus of the present invention were all less than 1 ppm.

今回開示された実施の形態および実施例はすべての点で例示であって制限的なものではないと考えられるべきである。本発明の範囲は上記した説明ではなくて特許請求の範囲によって示され、特許請求の範囲と均等の意味および範囲内でのすべての変更が含まれることが意図される。   It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

本発明のＳＯ3濃度計測装置はＳＯ3濃度を連続して計測することができるため、本発明のＳＯ3濃度計測装置はＳＯ3を含む排ガスを放出するプラント、特に発電プラントに好適に利用することができる。 SO 3 concentration measuring apparatus of the present invention it is possible to measure continuously the SO 3 concentration, SO 3 concentration measuring apparatus of the present invention is a plant for discharging exhaust gas containing SO 3, suitably used in particular power plant be able to.

本発明のＳＯ3濃度計測装置の好ましい一例の構成図である。It is a block diagram of a preferable example of the SO 3 concentration measuring apparatus of the present invention. （Ａ）は本発明に用いられる酸露点計の一例の概念図であり、（Ｂ）は（Ａ）に示す酸露点計のプローブ部の先端の平面図である。(A) is a conceptual diagram of an example of the acid dew point meter used for this invention, (B) is a top view of the front-end | tip of the probe part of the acid dew point meter shown to (A). 本発明に用いられる電気制御ユニットによる冷却用空気の放出量の制御の一例を示したフローチャートである。It is the flowchart which showed an example of control of the discharge | release amount of the cooling air by the electric control unit used for this invention. 本発明に用いられる水分計の一例の概念図である。It is a conceptual diagram of an example of the moisture meter used for this invention. 本発明に用いられる酸露点計と水分計のＳＯ3濃度と水分濃度の変化に対する出力変化を示した図である。It is a graph showing the output change with respect to change of SO 3 concentration and the moisture concentration of the acid dew point meter and moisture meter for use in the present invention.

符号の説明Explanation of symbols

１ 酸露点計、２ 水分計、３ 演算器、４ 煙道、５ 排ガス、６ プローブ部、７ 電気制御ユニット、８ 空気制御ユニット、９ 検出部、１０ 冷却用ノズル、１１ 冷却用空気、１２ Ｈ2ＳＯ4膜、１３ 熱電対、１４ リング電極、１５ 絶縁性部材、１６ 冷却用空気制御弁。 DESCRIPTION OF SYMBOLS 1 Acid dew point meter, 2 Moisture meter, 3 Calculator, 4 flue, 5 exhaust gas, 6 probe part, 7 electrical control unit, 8 air control unit, 9 detection part, 10 cooling nozzle, 11 cooling air, 12 H 2 SO 4 membrane, 13 thermocouple, 14 ring electrode, 15 insulating member, 16 air control valve for cooling.

Claims (3)

排ガス中のＳＯ3の濃度を計測するＳＯ3濃度計測装置であって、
前記排ガスの酸露点を計測する酸露点計測手段と、
前記排ガス中の水分濃度を計測する水分濃度計測手段と、
前記酸露点計測手段によって計測された酸露点と前記水分濃度計測手段によって計測された水分濃度とからＳＯ3濃度を演算するＳＯ3濃度演算手段と、
を含む、ＳＯ3濃度計測装置。 An SO 3 concentration measuring device for measuring the concentration of SO 3 in exhaust gas,
Acid dew point measuring means for measuring the acid dew point of the exhaust gas;
Moisture concentration measuring means for measuring the moisture concentration in the exhaust gas;
And SO 3 concentration calculating means for calculating a SO 3 concentration and a water concentration measured by the acid dew point by acid dew point measured by the measuring means and the moisture concentration measuring means,
SO 3 concentration measuring device. 前記酸露点計測手段による酸露点の計測時間と前記水分濃度計測手段による水分濃度の計測時間とのずれを補正してＳＯ3濃度が演算されることを特徴とする、請求項１に記載のＳＯ3濃度計測装置。 2. The SO 3 concentration according to claim 1, wherein the SO 3 concentration is calculated by correcting a deviation between a measurement time of the acid dew point by the acid dew point measurement unit and a measurement time of the water concentration by the moisture concentration measurement unit. 3 concentration measuring device. 前記ＳＯ3濃度演算手段によるＳＯ3濃度の演算は、
Figure 2005331408
 の式を用いて行なわれることを特徴とする、請求項２に記載のＳＯ3濃度計測装置。 The calculation of the SO 3 concentration by the SO 3 concentration calculating means is as follows:
Figure 2005331408
 The SO 3 concentration measuring apparatus according to claim 2, wherein the SO 3 concentration measuring apparatus is performed using the following formula.
JP2004150832A 2004-05-20 2004-05-20 Instrument for measuring so3 concentration Withdrawn JP2005331408A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004150832A JP2005331408A (en) 2004-05-20 2004-05-20 Instrument for measuring so3 concentration

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004150832A JP2005331408A (en) 2004-05-20 2004-05-20 Instrument for measuring so3 concentration

Publications (1)

Publication Number Publication Date
JP2005331408A true JP2005331408A (en) 2005-12-02

Family

ID=35486158

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004150832A Withdrawn JP2005331408A (en) 2004-05-20 2004-05-20 Instrument for measuring so3 concentration

Country Status (1)

Country Link
JP (1) JP2005331408A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010096561A (en) * 2008-10-15 2010-04-30 Fuji Electric Systems Co Ltd Calibration device for laser type gas analyzer
CN102661975A (en) * 2012-04-20 2012-09-12 华电环保系统工程有限公司 Method and device for continuously monitoring flue gas acid dew point at tail part of coal burning boiler on line
CN106248442A (en) * 2016-09-06 2016-12-21 山东能工低碳科技有限公司 SO in a kind of detection flue gas3method and system
CN106289884A (en) * 2016-09-06 2017-01-04 山东能工低碳科技有限公司 A kind of SO3the method and device of on-line checking
CN106353457A (en) * 2016-09-06 2017-01-25 山东能工低碳科技有限公司 Method and system for detecting flue gas SO3 based on salt absorption
CN109896505A (en) * 2019-04-17 2019-06-18 华能国际电力股份有限公司 Device and method for stably producing sulfur trioxide gas
CN112098461A (en) * 2020-09-24 2020-12-18 上海轻叶能源股份有限公司 Flue gas introducing method online water dew point acid dew point measuring device

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010096561A (en) * 2008-10-15 2010-04-30 Fuji Electric Systems Co Ltd Calibration device for laser type gas analyzer
CN102661975A (en) * 2012-04-20 2012-09-12 华电环保系统工程有限公司 Method and device for continuously monitoring flue gas acid dew point at tail part of coal burning boiler on line
CN102661975B (en) * 2012-04-20 2013-12-18 华电环保系统工程有限公司 Method and device for continuously monitoring flue gas acid dew point at tail part of coal burning boiler on line
CN106248442A (en) * 2016-09-06 2016-12-21 山东能工低碳科技有限公司 SO in a kind of detection flue gas3method and system
CN106289884A (en) * 2016-09-06 2017-01-04 山东能工低碳科技有限公司 A kind of SO3the method and device of on-line checking
CN106353457A (en) * 2016-09-06 2017-01-25 山东能工低碳科技有限公司 Method and system for detecting flue gas SO3 based on salt absorption
CN109896505A (en) * 2019-04-17 2019-06-18 华能国际电力股份有限公司 Device and method for stably producing sulfur trioxide gas
CN109896505B (en) * 2019-04-17 2023-11-03 华能国际电力股份有限公司 Device and method for stably generating sulfur trioxide gas
CN112098461A (en) * 2020-09-24 2020-12-18 上海轻叶能源股份有限公司 Flue gas introducing method online water dew point acid dew point measuring device
CN112098461B (en) * 2020-09-24 2021-07-06 上海轻叶能源股份有限公司 Flue gas introducing method online water dew point acid dew point measuring device

Similar Documents

Publication Publication Date Title
Dada et al. Formation and growth of sub-3-nm aerosol particles in experimental chambers
Fleig et al. Evaluation of SO3 measurement techniques in air and oxy-fuel combustion
US5017499A (en) Method for analyzing fluorine containing gases
JP6305945B2 (en) NOx concentration measurement system
Widmer et al. Practical limitation of mercury speciation in simulated municipal waste incinerator flue gas
Orsini et al. A new volatility tandem differential mobility analyzer to measure the volatile sulfuric acid aerosol fraction
JP2005331408A (en) Instrument for measuring so3 concentration
ES2616513T3 (en) Procedure and device for capturing measurement values and indication of measurement values
WO2010132180A1 (en) Generation of sulfur trioxide and sulfuric acid
KR101030931B1 (en) Measuring apparatus of hydrochloride among a continuous auto-measuring system for exhaust gas of chimney and measuring method for exhaust gas using the same
US20090229995A1 (en) Analysis of fluoride at low concentrations in acidic processing solutions
CN114184566B (en) Sulfate radical concentration measurement model applicable to different temperatures based on ultraviolet absorption spectrometry and verification method thereof
JP6643715B2 (en) Ozone measurement device
JP4206592B2 (en) SO3 densitometer
JP5466870B2 (en) Method and apparatus for measuring mercury concentration
TW200946765A (en) Engine oil consumption measurement method, engine oil consumption measuring device, and engine oil consumption measurement program
JP4443963B2 (en) Nitrogen dioxide standard gas production method
JP6381374B2 (en) Method and apparatus for measuring sulfur trioxide concentration
JP2014238316A (en) Sulfur trioxide concentration measuring apparatus and blue smoke alarm apparatus
RU2554663C1 (en) Electrochemical cell for analysing sulphur-containing gases
JP2001188038A (en) So3 densitometer
US5338685A (en) Process for the continuous quantitative determination of fluorine-containing compounds
JP2003014634A (en) So3/nh3 simultaneous and continuous densitometer
RU2314522C1 (en) Arrangement for measuring of the concentration of oxygen in gases
JP2018124089A (en) Mercury measuring apparatus

Legal Events

Date Code Title Description
A300 Withdrawal of application because of no request for examination

Free format text: JAPANESE INTERMEDIATE CODE: A300

Effective date: 20070807